Which of the following is correct statement?

Options

A. In metal carbonyl `d_(e-o)` increases compared to that of CO molecule
B. The pairs of compounds `[Cr(H_(2)O)_(6)]Cl_(3)and[CrCl_(3)(H_(2)O)_(3)].3H_(2)O` show hydrate isomerison
C. `d_(z)^(2)` orbital of central atom/ion is used in `dsp^(2)` hybridisation
D. Fac-mer isomers asscoiated with `Ma_(3),b_(3)` type compoud both optically active

Explanation

In the formation of metal carbonyls `d_(c-0)uarr`
b) `[Cr(H_(2)O)_(6)]Cl_(3)` and `[CrCl_(3)(H_(2)O)_(3)].3H_(2)O` show hydrate isomerison
c) In `dsp^(2)` hybridisation `d_(x^(2)-y^(2))` orbital can participate.
d) Fac-mer isomers associated with `Ma_(3)b_(3)` type compound donot show optical somerism.